Many energy suppliers source some of their electricity from so called Green sources such as wind or solar power. You can choose to 'use' this energy rather than the standard energy by paying the green energy tarrif. Although you don't get any difference in energy supply, your money will go towards the costs of producing this 'green' energy. Some companies only supply energy from green sources.

In essence, you pay for the amount of renewable energy that goes into the national grid for the amount you consume.

There are several websites that explain green energy and provide price comparisons too.

• http://www.uswitch.com/Energy/Green-Energy.html
• http://www.greenelectricity.org/